[This is a draft.  Over the next week or so I will be revising, adding links and making other versions to send to any news outlet that might take them.]

Here is the climate news.  The real climate news.

So far the world has warmed about 0.6°C.  If currently advised reductions of greenhouse gas emissions were realised there would still be a 90% chance global warming will exceed two degrees Celsius (2°C).  2°C used to be regarded as the threshold of “dangerous” climate change, but new science has shifted that threshold to only 1°C.  2°C is now regarded as the threshold of “extremely dangerous” climate change.  At that level, global warming effects would be widespread and severe.

However, somewhere between about 2°C and 4°C lurks a tipping point, beyond which global warming will run beyond human control, driven by natural feedback mechanisms that drive temperatures higher, perhaps to 6°C or 8°C, no-one knows.  4°C would already be “incompatible with an organised global community”.  Higher temperatures could result in the extinction half or more of the world’s species and much of the human population.

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